Lock mechanism



Aug. 20, 1957 H. W. YOUNG ETAL LOCK MECHANISM Filed March 16, 1955 2 Sheet s-Sheet 1 [NVENTORS Haiberf 4. Yaung/ BY Paul H. Greengaed fi' Za/M fifforney H. W. YOUNG ETAL Aug. 20, 1957 LOCK MECHANISM 2 Sheets-Sheet Filed March 16, 1955 INVENTORS Herben' W Young BY P u/ H. jgwwengaed A/zomey I United States Patent LOCK lVIECHANISM Herbert W. Young and Paul H. Grevengoed, Grand Rapids, Mich, assignors to Dexter industries, 122., Grand Rapids, Mich, a corporation of Michigan Application March 16, 1955, Serial No. 494,662

4 Claims. (Cl. 292169) This invention is associated particularly with a type of mechanism commonly referred to as an auxiliary lock. Locks of this category are commonly used in conjunction with conventional latches where it is desirable to supplement the operation of the latch with a lock which may be operable either with a different key mechanism from that of the latch, or operated exclusively from the inside with a separate knob.

In view of the number of instances in which it is not desirable to have an auxiliary lock mechanism functioning, modifications of the mechanism have been developed for maintaining the bolt in retracted condition. This invention relates to this aspect of the device.

The central feature of this invention lies in the relationship of a radius arm (controlled by a manually-operated. shaft or knob) and a cam surface on a retractor member which transfers forces from the radius arm to the bolt stem. This cam surface is formed in such a manner that a discontinuity is provided at a point engaged by the radius arm with the bolt in the fully retracted position. The effect of discontinuity is to create a jamming action between the retracting member and the radius arm such that the conventional biasing spring is incapable of moving the bolt to a projected position.

. The discontinuity, however, is formed in such a configuration that torque applied by the manually-operated knob or key will result in a pattern of forces at the discontinuity such that the radius arm can be moved in a direction to disengage itself from the discontinuity and permit projection of the bolt. Several subordinate features of construction are also provided by this invention which contribute to the operation outlined above.

The several features of the invention will be discussed in detail through an analysis of the particular embodiments illustrated in the accompanying drawings. Referring to the drawings,

Figure 1 presents a sectional elevation through the lock mechanism, with the bolt in the fully projected position.

Figure 2 presents a similar sectional elevation, with the mechanism in a condition which would be created when the bolt is partially retracted through beginning engagement with the keeper.

Figure 3 presents a view of the same mechanism, with the bolt in the fully retracted condition where it has been withdrawn by the operation of the radius arm, and is held in that condition through the interaction of the radius arm and the retractor.

Figure 4 illustrates the mechanism shown in the previous drawings at the moment of withdrawing the radius arm from engagement with the discontinuity of the cam surface of the retracting member.

Figure 5 presents a view on the plane 5-5 of Figure 1.

Figure 6 illustrates the same mechanism and condition as that of Figure 5, but with the position of the bolt and front plate rotated 180 about the axis of the mechanism with respect to the remainder of the housing.

Figure 7 presents a section on the plane 77 of Figure 5.

Referring to the drawings, a housing is provided which includes the opposite sections 10 and 11, which meet along a plane parallel to the axis of the lock, and a front plate 12. The front plate is provided with a boltreceiving aperture 13, and is secured to the flanges 14 and 15 of the collar 16 in a conventional manner. The collar 16 receives the forward portions 17 and 18 of the housing sections 10 and 11, respectively, and is provided with detents 19 and 20 for engagement with the apertures 21 and 22 in the housing sections. With this arrangement, the front plate and the collar 16 may be considered as rotatably mounted on the housing sections 10 and 11, with the engagement of the detent and the apertures 21 and 22 being left to determine the possible bolt positions which are 180 apart. In addition to providing the rotatable relationship between the front plate and the remainder of the housing, the collar 16 also serves to maintain the position of the housing sections, and establishes a snap-on assembly operation which is very economical and effective.

Since the bolt 23 is non-circular in cross section (due to the presence of the fiat 24-), the engagement of the bolt with the similarly-formed opening 23 in the front plate creates a slidable but non-rotative relationship between the bolt and the front plate. Rotation of the front plate with respect to the housing therefore carries the bolt with it.

The bolt 23 is fitted with a stem 25 which is secured to the bolt 23 by a pin 26. The stem 25 has an annular shoulder 27, and the inner end of the stem 25 (which is circular in cross section) is slideably received within the central aperture of a transverse plate 28. This plate is positioned through the engagement of the opposite tongues 2? and with suitable apertures in the housing sections 10 and 11, respectively. A spring 31 operates between the plate 28 and the annular shoulder 27 to continuously apply a biasing action urging the bolt 23 to the fully projected position.

The retraction of the bolt 23 to the position illustrated in Figure 4 may be accomplished in either of two ways. Figure 2 illustrates the condition in which the bolt has been shoved part way toward the retracted condition through exterior forces as might be applied by the keeper in the direction of the arrow 32. Figure 3 illustrates the fully retracted position created through the operation of the radius arm (manually controlled) generally indi cated at 33. The radius arm itself is preferably formed of two opposite components, each of which includes a hub portion 34 and 35, and a plate portion as shown at 35 and 37 (refer to Figure 5). The plate portions are both arranged perpendicularly to the axis of rotation of the radius arm unit which is established through the engagement of the hubs 34 and 35 with suitable apertures in the housing sections 10 and 11, respectively. Preferably, the hub and plate portions are formed out of a single piece of sheet metal, connected for convenience in manufacturing, by the strip 332:. The plate portions 36 and 37 are connected by a pin 38 which cooperates with a retracting member 39 for the transfer of forces from the pin to the bolt through the annular shoulder 27, the stem 25, and the pin 26.

The retracting member 39 is essentially a plate having the configuration indicated in Figures 1, 2, 3, and 4.

The forward portion of the retractor is provided with a notch 49 which receives the annular shoulder 27 'ofthe bolt stem 25, the forward wall of this notch being utilized to apply a rearward force to the shoulder '27, in response to rotation of the radius arm 33, to induce sliding movement of the bolt against the biasing effect. of the spring 31.

The retractor 39 is slideably received within a radiallyopen slot 41 in the transverse plate 28, and the rearward end of the retractor is formed in a cam surface 42 which cooperates with the pin 38 of the radius arm unit 33. Rotation of the radius arm 33 under forces applied at the driving slot43, in a clockwise direction, to the position illustrated 'in Figure 3 causes the pin 38to move along the cam surface '42 until it arrives in engagement with the discontinuity 44. The formation of the discontinuity 44 is such that while the spring 31 is not capable (no matter what strength it might have) of moving the bolt toward projected position, from the condition illustrated in Figure 3, it will not seriously interfere with the movement of the'radius arm in a counterclockwise direction under the application of torque from a manually- The sliding movement of the retractor 39 is guided through the engagement of the upper surface 45 of that member with the inside of the housing. Additionally, the ear 46 may be bent from the material of the housing section to stabilize the retractor 39 when in the fully retracted condition. If desired, the car 46 may also be 'positioned to act as a stop to limit the counterclockwise ing section 10 and 11, with the tabs being bent as shown in Figure 5 on assembly to lock the inner extremity of the housing sections together. This arrangement is conventional in the design of this type of mechanism.

The radially-open slot 41 permits the retracting member 39 to be assembled from the side; and when the notch 40 is in engagement with the shoulder 27, the surface 53 of the retractor function as a stop limiting the outward movement of the bolt. This arrangement produces an economical assembly operation in which the bolt stem can be inserted in the central opening in the plate 28 (with the spring 31 in position), followed by the placement of the retractor member. A sub-assembly is created thereby which can then be inserted in the housing as a unit.

The particular embodiments of the present invention which have been illustrated and discussed herein are for illustrative purposes only, and are not to be considered as a limitation upon the scope of the appended claims. In these claims, it is our intent to claim the entire invention disclosed herein, except as we are limited by the prior art.

We claim: a

1. A look, comprising: a housing having a front aperture; a bolt slideably mounted in said aperture; biasing means urging said bolt outwardly; bolt-retracting means includ ing a radius arm mounted in said housing for rotation on an axis which is transverse with respect to the sliding movement of said bolt, said radius arm having a pin adjacent the outer end thereof extending in a direction parallel to the axis of rotation of said radius arm;

a retractor member having the forward end thereof in engagement with a portion of said bolt, and the rearward ,end formed in a cam surface for cooperation with said pin, said cam surface having a depression adapted to 'receive a portion of said pin with said bolt in retracted position, and with said radius arm disposed substantially midway between a position parallel to said axis and perpendicular thereto, said depression being shaped to further being shaped to provide for the manual actuaoperated-operated member, delivered at the driving slot tion of said radius arm whereby said pin is moved out of engagement with said depression as said radius arm is rotated ina direction corresponding to the projected position of said bolt.

2. A lock, comprising: a housing having a front aperture; a bolt slideably mounted in said aperture; biasing means urging said bolt outwardly; bolt-retracting means including a radius arm mounted in said housing for rotation on an axis which is transverse with respect to the sliding movement of said bolt, said radius arm having an abutment adjacent the outer end thereof extending in a direction parallel to the axis of rotation of said radius arm; a retractor member having the forward end thereof in engagement with a portion of said bolt, and the rearward end formed in a cam surface for: cooperation with said abutment, said cam surface having a discontinuity adapted to receive a portion of said abutment with said bolt in retracted position, and with said radius arm disposed substantially midway between a position parallel to said axis and perpendicular thereto, said discontinuity being shaped to cause a jamming action between said radius arm and retractor member whereby said biasing means is restrained from moving said bolt, saiddiscontinuity and cam surface further being shaped to provide for the manual actuation of said radius arm whereby said abutment is moved out of engagement with said discontinuity as said radius arm is rotated in a direction corresponding to the projected position of said bolt. 7

3. A lock, comprising: a housing having a front aperture; a bolt slideably mounted in said aperture; biasing means urgingsaid bolt outwardly; bolt-retracting means including a radius arm mounted in said housing for rotatation on an axis which is transverse with respect to the sliding movement of said bolt; a retractor member having the forward end thereof in engagement with a portion of said bolt, and the rearward end formed in a cam surface for cooperation with said radius arm, said cam surface having a discontinuity adapted to receive a portion of said radius arm with said bolt in retracted position, and with said radius arm dis-posed substantially midway between a position parallel to said axis and perpendicular thereto, said discontinuity being shaped to cause a jamming action between said radius arm and retractor member whereby said biasing means is retrained from moving said bolt, said discontinuity and cam surface further being shaped to provide for the manual actuation :of said radius arm whereby said radius arm is moved out of engagement with said discontinuity as said radius arm is rotated in a direction corresponding to the projected position of said bolt.

4. A lock, comprising: an axially split housing having opposite sections, and having a front aperture; a transverse plate having portions engaging said sections and normally fixed with respect thereto, and having a central hole and also a radially-open slot intersecting the edge of said plate; a bolt slideably mounted in said aperture, and having a stem engaging said hole; biasing means urging said bolt outwardly, and acting between said plate and a surface fixed with respect to said bolt; bolt-retracting means including a radius arm mounted in said housing for rotation on an axis which is transverse with respect to the sliding movement of said bolt; and a retractor member slideably receivedin said radially-open slot and having the forward end thereof in engagement with a portion of said bolt, the rearward end of said retractor member being formed for cooperation with said radius arm, said retractor member also having a surface disposed to engage the inner surface of said plate with said bolt in projected position.

References Cited in the file of this patent UNITED STATES PATENTS Backhouse Oct. 3, 1939 

